| 摘要 |
PURPOSE:To quickly detect service interruption by presetting a microcomputer, for instance, the interruption of a rectangular wave input is to be service interruption since a rectangular wave input to a microcomputer is interrupted when service interruption is brought about. CONSTITUTION:The secondary output of a transformer 10 is transferred through a full-wave rectification circuit 11, a smoothing capacitor 12 and a stabilized power supply to deliver d.c. voltage (Vcc). A center tap 14 is provided in the secondary winding of the transformer 10, and the voltage taken out from the center tap 14 is inputted to a waveform shaping circuit 18 through a diode 15 and resistors 16, 17 for dividing voltage. The half-wave alternating current output voltage of the diode is shaped into a rectangular wave by the waveform shaping circuit as shown in Fig. 3 and then inputted to a microcomputer 19. |
